Long-Term Follow-Up of Preoperative Pelvic Radiation Therapy and Concomitant Boost Irradiation in Locally Advanced Rectal Cancer Patients: A Multi-Institutional Phase II Study (KROG 04-01)

• Published in: International journal of radiation oncology, biology, physics Vol. 84; no. 4; pp. 955 - 961
• Main Authors: Lee, Jong Hoon, M.D, Kim, Dae Yong, M.D, Nam, Taek-Keun, M.D, Yoon, Sei-Chul, M.D, Lee, Doo Seok, M.D, Park, Ji Won, M.D, Oh, Jae Hwan, M.D, Chang, Hee Jin, M.D, Yoon, Mee Sun, M.D, Jeong, Jae-Uk, M.D, Jang, Hong Seok, M.D
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 15-11-2012; Elsevier
• Subjects: 5-Fluorouracil; Adult; Aged; Aged, 80 and over; Antimetabolites, Antineoplastic - therapeutic use; Biological and medical sciences; chemoradiation therapy; Chemoradiotherapy - adverse effects; Chemoradiotherapy - methods; Chemoradiotherapy - mortality; CITROVORUM FACTOR; CLASSIFICATION; Disease-Free Survival; Dose Fractionation; Drug Administration Schedule; Female; Fluorouracil - administration & dosage; Follow-Up Studies; Gastroenterology. Liver. Pancreas. Abdomen; Hematology, Oncology and Palliative Medicine; HISTOLOGY; Humans; IRRADIATION; Leucovorin - administration & dosage; Male; Medical sciences; Middle Aged; MULTIVARIATE ANALYSIS; NEOPLASMS; PATIENTS; PELVIS; Preoperative Care - methods; Prognostic factor; Prospective Studies; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; Radiotherapy, Adjuvant - adverse effects; Radiotherapy, Adjuvant - methods; Rectal cancer; Rectal Neoplasms - mortality; Rectal Neoplasms - pathology; Rectal Neoplasms - therapy; RECTUM; Remission Induction - methods; Response; Small field; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Survival Rate; TOXICITY; Tumors; URACILS; Response; Prognostic factor; Small field; Rectal cancer; chemoradiation therapy; Rectal disease; Prognosis; Overdosing; Chemoradiotherapy; Cancerology; Pelvic cavity; Phase II trial; Intestinal disease; Anorectal disease; Human; Malignant tumor; Rectum cancer; Radiotherapy; Long term; Chemotherapy; Treatment; Follow up study; Digestive diseases; Combined treatment; Locally advanced stage; Predictive factor; Cancer
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2012.01.045

Purpose To perform a prospective phase II study to investigate the efficacy and safety of preoperative pelvic radiation therapy and concomitant small-field boost irradiation with 5-fluorouracil and leucovorin for 5 weeks in locally advanced rectal cancer patients. Methods and Materials Sixty-nine patients with locally advanced, nonmetastatic, mid-to-lower rectal cancer were prospectively enrolled. They had received preoperative chemoradiation therapy and total mesorectal excision. Pelvic radiation therapy of 43.2 Gy in 24 fractions plus concomitant boost radiation therapy of 7.2 Gy in 12 fractions was delivered to the pelvis and tumor bed for 5 weeks. Two cycles of 5-fluorouracil and leucovorin were administered for 3 days in the first and fifth week of radiation therapy. The pathologic response, survival outcome, and treatment toxicity were evaluated for the study endpoints. Results Of 69 patients, 8 (11.6%) had a pathologically complete response. Downstaging rates were 40.5% for T classification and 68.1% for N classification. At the median follow-up of 69 months, 36 patients have been followed up for more than 5 years. The 5-year disease-free survival (DFS) and overall survival rates were 66.0% and 75.3%, respectively. Higher pathologic T ( P = .045) and N ( P = .032) classification were significant adverse prognostic factors for DFS, and high-grade histology was an adverse prognostic factor for both DFS ( P = .025) and overall survival ( P = .031) on the multivariate analysis. Fifteen patients (21.7%) experienced grade 3 or 4 acute toxicity, and 7 patients (10.1%) had long-term toxicity. Conclusion Preoperative pelvic radiation therapy with concomitant boost irradiation with 5-fluorouracil and leucovorin for 5 weeks showed acceptable acute and long-term toxicities. However, the benefit of concomitant small-field boost irradiation for 5 weeks in rectal cancer patients was not demonstrated beyond conventional irradiation for 6 weeks in terms of tumor response and survival.